I honestly don't know where those thoroughly unfunny gayness jokes about them stem from, but to each their own, I guess...
My favourite album (not just my favourite BG album, but my favourite album, period) still is "Imaginations from the Other Side"... in fact, the first metal album I heard in my life. Every song a little work of art, composed perfectly, even better live.
"A Night at the Opera" is a close second, I've spent so much time dissecting every litte detail and I still love it. "Age of False Innocence" or "And then there was Silence" (which is great live, by the way) stand among their best songs ever.
"Nightfall in Middle-Earth" comes in third place... intricate arrangements and the most Queen-ish vocals ever not found on a Queen record. I'd love to see this one performed on stage as a whole.